1. Field of the Invention
This invention relates to improvements in the system of navigation lights for barges under tow in the inland waters of the United States. In particularly, this invention advances a system incorporating totally self-contained portable light units with the additional feature of being able to be nested one inside the other for easy handling and storage.
2. Prior Art
United States law requires that vessels under tow upon the inland waters of the United States display navigation lights when being towed from sunset to sunrise. The actual navigation lights required are dependent upon the configuration of the tow. The visible range of the required lights is dependent upon the length of the tow. The visible arc of the horizon of the required light is dependent upon the nature of the light. The specifics of each of the foregoing parameters is set forth in Public Law 95-591: "Inland Navigation Rules Action of 1980".
The practice of the marine industry on the inland waters of the United States is to use portable lights to meet the above stated requirements.
In some instances, a portable unit containing a lamp, the appropriate lens and the necessary screen is mounted on a fixed support and connected to an external power source. The power source is usually located on the towing vessel and in many instances is integral with the towing vessels own electrical power system. The transmission system is usually a portable electrical cable laid out across the weather deck of the towed vessel. In other instances a lamp and lens unit is affixed to a six bolt battery and electrically connected by small wire leads or "pigtails". This composite is lashed into position on the towed vessel.
In both instances the attempt to satisfy the statutory requirements results in a cumbersome system.
The patents listed below were noted in a search and may be considered of interest:
U.S. Pat. Nos.
1,618,816; 1,822,619; 2,420,634; 2,875,324; 3,403,249; 3,456,102; 3,706,882; 3,793,515; 3,944,806.
3. Summary Discussion of the Invention
It is therefore an object of the present invention to provide a totally self-contained navigation light system wherein each unit contains its own power supply, light activating mechanism, lamp, lens, screens and means for affixing the unit to the towed vessel.
It is another object of the present invention to incorporate in each unit an integral carrying handle.
It is still another object of the present invention to configure each unit so that the required units comprising the system will nest one inside the other with their respective handles coinciding as one thereby permitting the carrying of the nested units as one.